Use of a Raman microscope to obtain useful SERS signals with colloidal gold

Gold nanoparticles were synthesized according to a modified Turkevich method thiosulfate as the reducing agent and sulfate anions as a stabilizer. The size distribution of the resulting nanoparticles was analyzed using transmission electron microscopy and were found to be on the order of 40 nm in diameter and not very monodisperse. Nanoparticles were used with a Raman microscope to produce a SERS signal from organic dyes such as Rhodamine 6 G. As compared to regular Raman spectrometers, it was found that the Raman microscope would only give a useful signal after a specific method that includes drying the nanoparticles on a charged slide and then taking the spectrum directly after analyte addition. The goal of this research is to investigate a new method of recombinant EPO detection. In order to make progress, steps were taken to attach EPO-mimicking antibodies onto microscope slides and create antibody-nanoparticle conjugates.